Anyone who’s ever worn a dress can agree on one thing: it’s pretty much the most comfortable piece of clothing on the planet. Not only does it simplify the whole getting-dressed thing, but it adds an air of polish without actually requiring any extra primping. What you may not know? There are a few defining factors that make each dress fit for a specific occasion – all you need to do is learn how to spot them. Use this quick-reference guide to help you decode these one-piece wonders.